Stay-bolt.



Patented Aug. I, I899.

m. 630,l6l.

J. M. BAILEY.

STAY BOLT.

(Application filed Feb. 24, 1898.)

"No Model.)

JAMES M. BAILEY, OF ALLEGHENY, PENNSYLVANIA.

STAY-BO LT.

SPECIFICATION forming part of Letters Patent No. 630,161, dated August 1, 1899.

Application filed February 24,1898. Serial No. 671,473. (No model.)

To all whmn it 7121a con/007%:

Be it known that I, JAMES M. BAILEY, a resident of Allegheny, in the county of Allegheny and State of Pennsylvania, have invented a new and useful Improvement in Stay-Bolts; and I do hereby declare the following to be a full, clear, and exact description thereof.

My invention relates to stay-bolts, and more particularly to such as are employed for connecting two plates so as to make them mutually sustaining against internal pressure, as in the case of the 'water and steam spaces of locomotive and other boilers. It is the general custom at present in the construction of such water and steam spaces to employ solid stay-bolts of wrought-iron or steel of a uniform diameter. Longlengths of wrought-iron or steel rods are manufactured to supply the demand for these stay-bolts, and the locomotive or boiler manufacturer cuts the stay-bolts from these rods as he needs them of the proper length, according to the distance between the two plates to be connected. The stay-bolts thus cut are inserted in the openings formed for them in the plates, and the ends are then riveted. Although these stay-bolts or the rods from which they are out are subjected to a severe test before they are used in order to determine whether they will stand the severe strains which they are compelled to meet, yet such tests will not insure against the breaking of said bolts. Taking the locomotive as an illustration, the inspections of same from time to time disclose the breakage of these stay-bolts, and in many cases to such an extent that the further use of the boilerspaoe in its weakened state would be attended with great danger of an explosion. \Vhere the stay-bolts are made in the usual way and riveted in the manner described, there is nothing to indicate from the exterior of the Waterspace whether any of said bolts are broken. An explosion may take place before an inspection has been made.

To these ends my invention consists in a stay-bolt comprising the novel features hereinafter set forth and claimed.

To these ends my invention comprises, generally stated, a stay-bolt having threaded end portions adapted to enter and engage threaded openings in the plates, one of said end portions having an angular shoulder formed integral therewith and extending beyond the threads, so as to engage the outer face of the plate adjacent thereto, whereby it is possible to grasp said shoulder and turn the bolt after said bolt'has been secured in place.

To enable others skilled in the art to make and use my invention, I will describe the same more fully, referring to the accompanying drawings, in which- Figure 1 is a perspective view of my improved stay-bolt. Fig. 2 is a view of same in connection with a portion of two plates forming a water or steam space. Fig. 3 is a face view of the front plate, showing the stay-bolt inserted therein. Fig. 4 is a like view of the inner plate.

Like letters of reference indicate like parts in each.

In the drawings the letters a a designate portions of two boiler or like plates to be connected, and for convenience I will refer to same as the water-space of a locomotive, although I do not Wish to limit my invention to this particular application of it. These plates at a are provided with threaded openings a".

The stay-bolt B, which may be constructed of wrought-iron,steel, or other suitable metal, has the threaded end portions 1) 1) adapted to enter and engage the threaded openings a in the plates CL a. The shank b of the stay-bolt, intermediate the threaded portions 1) b, is of smaller diameter than the smallest diameter of the threaded portions 1) b--that is, the diameter at the base of the threads, Passages c c are formed in the stay-bolt, said passages being preferably central of said bolt and extending within the same to a point beyond the threaded portions 1) 1'). One end of the stay-bolt has the shoulder d formed thereon, said shoulder being preferably polygonal in form, so that it may be readily grasped by a wrench or like tool, and in addition to said shoulder d said stay-bolt has the square head e, to be grasped by the tool for purposes of turning said bolt when said bolt is being screwed into place, said head e being cut off when the bolt is secured in place.-

In embodying the invention in practical form the stay-bolts will be made and furnished to the trade in different sizes complete and ready for use. The stay-bolts will be screwed into the openings a in the manner shown, the inner ends thereof being riveted as at c, and the shoulder (Z of the outer end pressing against the outer plate (1 serves to make a tight connection.

In the water-space of a locomotive the inner plate a, being next to the fire, moves up and down, owing to the expansion and contraction of said plate caused by the intense heat and the subsequent cooling of said plate. This movement on the part of the plate a will throw a strain on the stay-bolt, the tendency of such strain being to bend the same. If this strain is sufficient to break or crack the stay-bolt at the threaded portion of either end, such crack or break will permit the water and steam to escape by the passages e c to the exterior of the plates. This escaping water and steam Will at once attract attention and indicate that a stay-bolt is defective. A closer inspection will reveal just which staybolt has given Way. I do not claim this feature as new or part of my invention. However, to reduce the liability of the stay-bolts breaking at their threaded portions is the purpose of the diminished diameter of the shank 11 By having this shank of smaller diameter than the smallest diameter of the threaded portions 1) b the movement of the plate a, will tend to bend the stay-bolt at its smallest diameter. Consequently the strain will be transferred from the ends to the central portion stay-bolts to discover Whether they are sound one may grasp the shoulderdof the stay-bolt with a wrench and by turning the same tell whether the stay-bolt is Whole. If upon turning the outer end the inner end also turns, then it is proof that the stay-bolt is perfect; but if, on the contrary, the inner end does not turn then it follows that a break has occurred. This manner of testing can be accomplished without having to gain access to the interior of the water-space.

What I claim as my invention, and desire to secure by Letters Patent, is

As a new article of manufacture, a stay-bolt having threaded end portions, and an angular shoulder at the extreme end of one of the threaded portions and integral therewith,said shoulder extending out beyond the line of said threads at right angles to the axial line of said bolt, and an angular head extending beyond said shoulder, substantially as set forth.

In testimony whereof I, the said JAMES M. BAILEY, have hereunto set my hand.

JAMES M. BAILEY.

l/Vitnessesz RoBT. D. TOTTEN, ROBERT C. TOTTEN. 

